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Sharper shots with
Canon’s Av mode
Use Aperture Priority mode when light levels inconveniently change
A
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futurenet.comperture Priority (Av) mode is
one of the most popular
creative modes, allowing
photographers to choose the depth of
field, while the camera chooses
metering and shutter speed. One of the
limitations is the shutter speed range
extends as far as 30 secs. As a result
when shooting in low light, blurred
photos often result due to camera
shake and subject movement.
One option for most cameras is
to set the camera to Auto ISO. This
causes the camera to factor in the
focal length of the lens and raises the
ISO to avoid camera shake as much
as possible, and especially in low-light
situations. But if you shoot with a
24mm lens a 1/30 sec shutter speed
is likely, which is still a little slow for
photos with moving subjects.More advanced cameras provide
extra ways to limit the shutter speed
with Av. Change the minimum shutter
speed for Auto ISO with program or Av.
In Auto ISO the camera uses the focal
length of the lens to determine the
minimum shutter speed, but this
setting lets you increase the minimum
shutter speed, either in relation to the
focal length or a selected value. In
low-light with flash the ISO is locked
to ISO400, which renders this option
slightly less useful. The camera ignores
your minimum shutter speed setting,
and chooses shutter speeds for a
correct exposure with ISO400.
One of the best ways to limit the
shutter speed in Av is by limiting the
shutter speed range. Once you limit the
range, you also need to activate safety
shift with ISO to avoid underexposedshots in low-light. With ISO safety shift
activated the camera will override the
selected ISO when the shutter speed
reaches the minimum you’ve chosen. If
you use flash, then it is best to choose
a fixed ISO, not Auto ISO. Then ISO will
be adjusted and not limited to ISO400
with flash. If you pick this method, use
a custom shooting mode, C1/C2/C3 to
make a copy of Av and implement the
settings. Other modes outside of the
custom mode will then allow the full
range of shutter speeds to be selected.Limit shutter speed range, and enable safety
shift with iSO to avoid slow shutter speedsUse Aperture Priority (Av) to
control depth of field with
custom settings to avoid
slow shutter speeds